The invention relates to a misfuelling prevention device. Such a device acts to stop a specific fuel from being accidentally added to the fuel tank of an engine which has not been developed for such specific fuel. For example, such a device acts to stop automotive diesel fuel from being accidentally added to the fuel tank of a gasoline-fuelled vehicle at a retail filling station.
Diesel fuel is being used in increasing quantities by the private motorist, who can now choose a compression-ignition engine as an option with many cars. This has encouraged changes in the siting of delivery pumps at retail stations, and whereas previously the diesel pump would be remotely situated it will now often be found next to its gasoline counterparts. The motorist must make an active decision as to which pump to select when purchasing fuel, and failure to do so could result in misfuelling. The principal problem arises with the drivers of conventional gasoline-fuelled vehicles who draw up to diesel pumps unaware that any fuel other than gasoline is available; the converse problem of drivers attempting to put gasoline into diesel tanks is much rarer, presumably because the drivers of diesel-fuelled vehicles, who are in the minority, are most accustomed to being selective in their refuelling. This problem at best, causes considerable disruption to the business of the retail station, and at worst could damage a customer's vehicle, resulting in a claim for repairs.
There are several ways in which this problem could be tackled. A direct alternative would be to ensure physical incompatibility between, for example, the fillers of gasoline and diesel cars, so that the nozzle of a diesel pump simply could not be used to refill a gasoline vehicle. This, however, would require the participation of third parties, certainly the vehicle manufacturers to ensure that common standards are agreed upon and enforced. Another possibility would be to include a sensor to sample the contents of the fuel tank before filling to confirm that the fuel is compatible before allowing fresh fuel to be dispensed.
Therefore, it is an object of the invention to provide a simple and convenient method and system for misfuelling prevention which can be used as a safeguard against the accidental misfuelling of automotive or other engines, which is becoming more common with the increased use of fuels other than gasoline for vehicles, and which causes great inconvenience and possibly engine damage.